Patents by Inventor G. Reza Chaji

G. Reza Chaji has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9281330
    Abstract: One sensor pixel includes amplifying transistor, coupled between first bias line and data line; switch transistor, operated by control line and coupled between data line and gate of amplifying transistor; storage capacitor, coupled to second bias line; and sensor being coupled to gate of amplifying transistor. Another sensor pixel includes first amplifying transistor coupled between first bias line and data line; second amplifying transistor being coupled between second bias line and data line; switch transistor being operated by control line and being coupled between data line and gates of first and second amplifying transistors; storage capacitor coupled to gates of first and second amplifying transistors; and sensor coupled to gates of first and second amplifying transistors. Trap-assisted absorption, variable capacitor described for sensor pixels, and also biasing to reduce flicker and aging, and to compensate for aging, described for sensor pixels.
    Type: Grant
    Filed: September 27, 2014
    Date of Patent: March 8, 2016
    Inventors: Arokia Nathan, G. Reza Chaji
  • Patent number: 9117400
    Abstract: A system for maintaining a substantially constant display white point over an extended period of operation of a color display formed by an array of multiple pixels in which each of the pixels includes multiple subpixels having different colors, and each of the subpixels includes a light emissive device. The display is generated by energizing the subpixels of successively selected pixels, and the color of each selected pixel is controlled by the relatives levels of energization of the subpixels in the selected pixel. The degradation behavior of the subpixels in each pixel is determined, and the relative levels of energization of the subpixels in each pixel are adjusted to adjust the brightness shares of the subpixels to compensate for the degradation behavior of the subpixels. The brightness shares are preferably adjusted to maintain a substantially constant display white point.
    Type: Grant
    Filed: June 16, 2010
    Date of Patent: August 25, 2015
    Assignee: Ignis Innovation Inc.
    Inventors: G. Reza Chaji, Joseph Marcel Dionne, Abbas Hormati, Tong Liu, Stefan Alexander, Arokia Nathan
  • Publication number: 20150048241
    Abstract: One sensor pixel includes amplifying transistor, coupled between first bias line and data line; switch transistor, operated by control line and coupled between data line and gate of amplifying transistor; storage capacitor, coupled to second bias line; and sensor being coupled to gate of amplifying transistor. Another sensor pixel includes first amplifying transistor coupled between first bias line and data line; second amplifying transistor being coupled between second bias line and data line; switch transistor being operated by control line and being coupled between data line and gates of first and second amplifying transistors; storage capacitor coupled to gates of first and second amplifying transistors; and sensor coupled to gates of first and second amplifying transistors. Trap-assisted absorption, variable capacitor described for sensor pixels, and also biasing to reduce flicker and aging, and to compensate for aging, described for sensor pixels.
    Type: Application
    Filed: September 27, 2014
    Publication date: February 19, 2015
    Inventors: Arokia Nathan, G. Reza Chaji
  • Patent number: 8947571
    Abstract: A sensor pixel including a sensor, charge storage, a reset block having a reset input, readout block, and a charge leakage gain adjustment block having a gain adjustment control input. The sensor, charge storage, reset block, readout block, and charge leakage gain adjustment block are each operatively connected to a node. Adjusting the gain of a sensor pixel by storing charge from a sensor in a charge storage connected to a node, leaking charge from the charge storage to reduce the charge at a node, and reading out a state of the pixel represented by the charge of a node.
    Type: Grant
    Filed: April 9, 2009
    Date of Patent: February 3, 2015
    Inventors: G. Reza Chaji, Arokia Nathan
  • Patent number: 8872095
    Abstract: One sensor pixel includes amplifying transistor, coupled between first bias line and data line; switch transistor, operated by control line and coupled between data line and gate of amplifying transistor; storage capacitor, coupled to second bias line; and sensor being coupled to gate of amplifying transistor. Another sensor pixel includes first amplifying transistor coupled between first bias line and data line; second amplifying transistor being coupled between second bias line and data line; switch transistor being operated by control line and being coupled between data line and gates of first and second amplifying transistors; storage capacitor coupled to gates of first and second amplifying transistors; and sensor coupled to gates of first and second amplifying transistors. Trap-assisted absorption, variable capacitor described for sensor pixels, and also biasing to reduce flicker and aging, and to compensate for aging, described for sensor pixels.
    Type: Grant
    Filed: December 4, 2013
    Date of Patent: October 28, 2014
    Inventors: Arokia Nathan, G. Reza Chaji
  • Patent number: 8860636
    Abstract: A method and system for driving a light emitting device display is provided. The system provides a timing schedule which increases accuracy in the display. The system may provide the timing schedule by which an operation cycle is implemented consecutively in a group of rows. The system may provide the timing schedule by which an aging factor is used for a plurality of frames.
    Type: Grant
    Filed: September 29, 2010
    Date of Patent: October 14, 2014
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, G. Reza Chaji
  • Publication number: 20140091207
    Abstract: One sensor pixel includes amplifying transistor, coupled between first bias line and data line; switch transistor, operated by control line and coupled between data line and gate of amplifying transistor; storage capacitor, coupled to second bias line; and sensor being coupled to gate of amplifying transistor. Another sensor pixel includes first amplifying transistor coupled between first bias line and data line; second amplifying transistor being coupled between second bias line and data line; switch transistor being operated by control line and being coupled between data line and gates of first and second amplifying transistors; storage capacitor coupled to gates of first and second amplifying transistors; and sensor coupled to gates of first and second amplifying transistors. Trap-assisted absorption, variable capacitor described for sensor pixels, and also biasing to reduce flicker and aging, and to compensate for aging, described for sensor pixels.
    Type: Application
    Filed: December 4, 2013
    Publication date: April 3, 2014
    Inventors: Arokia Nathan, G. Reza Chaji
  • Patent number: 8614652
    Abstract: A light emitting device display, its pixel circuit and its driving technique is provided. The pixel includes a light emitting device and a plurality of transistors. A bias current and programming voltage data are provided to the pixel circuit in accordance with a driving scheme so that the current through the driving transistor to the light emitting device is adjusted.
    Type: Grant
    Filed: April 17, 2009
    Date of Patent: December 24, 2013
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, G. Reza Chaji, Stefan Alexander
  • Publication number: 20130299680
    Abstract: One sensor pixel includes amplifying transistor, coupled between first bias line and data line; switch transistor, operated by control line and coupled between data line and gate of amplifying transistor; storage capacitor, coupled to second bias line; and sensor being coupled to gate of amplifying transistor. Another sensor pixel includes first amplifying transistor coupled between first bias line and data line; second amplifying transistor being coupled between second bias line and data line; switch transistor being operated by control line and being coupled between data line and gates of first and second amplifying transistors; storage capacitor coupled to gates of first and second amplifying transistors; and sensor coupled to gates of first and second amplifying transistors, Further sensor pixel includes two photo transistors connected to first and second bias lines.
    Type: Application
    Filed: July 15, 2013
    Publication date: November 14, 2013
    Inventors: Arokia Nathan, G. Reza Chaji
  • Patent number: 8487231
    Abstract: One sensor pixel includes amplifying transistor, coupled between first bias line and data line; switch transistor, operated by control line and coupled between data line and gate of amplifying transistor; storage capacitor, coupled to second bias line; and sensor being coupled to gate of amplifying transistor. Another sensor pixel includes first amplifying transistor coupled between first bias line and data line; second amplifying transistor being coupled between second bias line and data line; switch transistor being operated by control line and being coupled between data line and gates of first and second amplifying transistors; storage capacitor coupled to gates of first and second amplifying transistors; and sensor coupled to gates of first and second amplifying transistors. Further sensor pixel includes two photo transistors connected to first and second bias lines.
    Type: Grant
    Filed: December 17, 2007
    Date of Patent: July 16, 2013
    Inventors: Arokia Nathan, G. Reza Chaji
  • Patent number: 8477121
    Abstract: A method and system for operating a pixel array having at least one pixel circuit is provided. The method includes repeating an operation cycle defining a frame period for a pixel circuit, including at each frame period, programming the pixel circuit, driving the pixel circuit, and relaxing a stress effect on the pixel circuit, prior to a next frame period. The system includes a pixel array including a plurality of pixel circuits and a plurality of lines for operation of the plurality of pixel circuits. Each of the pixel circuits includes a light emitting device, a storage capacitor, and a drive circuit connected to the light emitting device and the storage capacitor. The system includes a drive for operating the plurality of lines to repeat an operation cycle having a frame period so that each of the operation cycle comprises a programming cycle, a driving cycle and a relaxing cycle for relaxing a stress on a pixel circuit, prior to a next frame period.
    Type: Grant
    Filed: April 18, 2007
    Date of Patent: July 2, 2013
    Assignee: Ignis Innovation, Inc.
    Inventors: Arokia Nathan, G. Reza Chaji
  • Patent number: 8471875
    Abstract: A display system includes a driver for operating a panel having a plurality of pixels arranged by a plurality of first lines and at least one second line The driver includes a driver output unit for providing to the panel a single driver output for activating the plurality of first lines, the single driver output being demultiplexed on the panel to activate each first line.
    Type: Grant
    Filed: July 28, 2009
    Date of Patent: June 25, 2013
    Assignee: Ignis Innovation Inc.
    Inventors: G. Reza Chaji, Kongning Li, Vasudha Gupta, Arokia Nathan
  • Patent number: 8358299
    Abstract: A display system, a driver for driving the display array, method of operating the display system and a pixel circuit in the display system are provided. The driver includes: a bidirectional current source having a convertor coupling to a time-variant voltage, for converting the time-variant voltage to the current. The pixel circuit includes: a transistor for providing a pixel current to a light emitting device; and a storage capacitor electrically coupling to the transistor, the capacitor coupling to a time-variant voltage in a predetermined timing for providing a current based on the time-variant voltage.
    Type: Grant
    Filed: December 8, 2009
    Date of Patent: January 22, 2013
    Assignee: Ignis Innovation Inc.
    Inventors: G. Reza Chaji, Arokia Nathan
  • Patent number: 8334863
    Abstract: A display system and a device having the display system are provided. The display system includes: a pixel area on which a pixel is formed; a substrate having a top side and a back side opposite to the top side, and a plurality of edges between the top side and the back side, the substrate being a main substrate on which the pixel area being formed or a sealing substrate; and a solar cell area having at least one solar cell integrated on a peripheral of the pixel area, the edge of the substrate or a combination thereof. The display system includes: a pixel area on a display substrate, including: a transparent electrode; and an emissive device for emitting a light, the transparent electrode and the emissive device being aligned in series on the display substrate, a solar cell placed behind the transparent electrode, for making the transparent electrode non-reflective to the emissive device.
    Type: Grant
    Filed: December 23, 2008
    Date of Patent: December 18, 2012
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, G. Reza Chaji
  • Patent number: 8299984
    Abstract: A display system and method for the same is provided. A display includes a plurality of pixels, each having a light emitting device and a driving transistor for driving the light emitting device, the driving transistor and the light emitting device being coupled in series between a first power supply and a second power supply. The method includes: at a first frame, programming a pixel with a first programming voltage different from a programming voltage for a valid image, and charging at least one of the first power supply and the second power supply so that at least one of the driving transistor and the light emitting device is under a negative bias.
    Type: Grant
    Filed: April 15, 2009
    Date of Patent: October 30, 2012
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, G. Reza Chaji, J. Marcel Dionne
  • Patent number: 8253665
    Abstract: A method and system for driving an active matrix display is provided. The system includes a drive circuit for a pixel having a light emitting device. The drive circuit includes a drive transistor for driving the light emitting device. The system includes a mechanism for adjusting the gate voltage of the drive transistor.
    Type: Grant
    Filed: January 9, 2007
    Date of Patent: August 28, 2012
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, G. Reza Chaji
  • Patent number: 8223177
    Abstract: A method and system for driving a pixel circuit in an active matrix display is provided. The system implements a feedback driving scheme to enhance programming speed of the pixel circuit. The system includes a column driver for driving the pixel circuit with feedback. A controller controls a signal on a programming signal line during a programming cycle. For example, the driver may include a model for reducing the settling time of a pixel current. During the programming mode, an accelerating pulse may be provided to accelerate the programming of the pixel circuit.
    Type: Grant
    Filed: July 6, 2006
    Date of Patent: July 17, 2012
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, Shahin Jafarabadiashtiani, G. Reza Chaji
  • Patent number: 8188946
    Abstract: A method and system for compensation for luminance degradation in electro-luminance devices is provided. The system includes a pixel circuit having a light emitting device, a storage capacitor, a plurality of transistors, and control signal lines to operate the pixel circuit. The storage capacitor is connected or disconnected to the transistor and a signal line(s) when programming and driving the pixel circuit.
    Type: Grant
    Filed: September 12, 2006
    Date of Patent: May 29, 2012
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, G. Reza Chaji, Shahin Jafarabadiashtiani
  • Publication number: 20120013581
    Abstract: A method and system for driving an active matrix display is provided. The system includes a drive circuit for a pixel having a light emitting device. The drive circuit includes a drive transistor for driving the light emitting device. The system includes a mechanism for adjusting the gate voltage of the drive transistor.
    Type: Application
    Filed: September 23, 2011
    Publication date: January 19, 2012
    Applicant: Ignis Innovation Inc.
    Inventors: Arokia Nathan, G. Reza Chaji
  • Patent number: 8026876
    Abstract: A system and method are disclosed for determining a pixel capacitance. The pixel capacitance is correlated to a pixel age to determine a current correction factor used for compensating the pixel drive current to account for luminance degradation of the pixel that results from the pixel aging.
    Type: Grant
    Filed: August 15, 2007
    Date of Patent: September 27, 2011
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, G. Reza Chaji